1998 GMC Safari Owner's Manual - Page 230

a CAUTION: A vehicle can fall froma car carrierif it isn't adequately secured. This cause a collision, can serious personal injury and vehicle damage. The vehicle should be tightly secured with chains or steel cables before is transported. it Don't use substitutes (ropes, leather straps, canvas webbing, etc.)that can be cut by sharp edges underneath the towed vehicle. When your vehicle is being towed, have the ignition key in theOFF position. The steering wheel should be clamped ina straight-ahead position, with a clamping device designed for towing service. not Do use the vehicle's steering column lock for this. The transmission shouldbe in NEUTRAL(N) and the parking brake released. If your vehicle hasthe all-wheel-drive option,it can only be towed with allfour wheels off the ground. A dolly must be used under the unraised wheels must a when towing or the vehicle be transported on flat bedcarrier, Don't have your vehicle towed with the wheels in contact with the ground it has all-wheel drive.If if a vehicle with all-wheel drive must be towed with sling-type or wheel-lift equipment, then either the front or rear wheels mustbe supported ona dolly. NOTICE: If'your vehicle has all-wheel drive,do not have it towed withthe wheels in contact withthe ground or vehicle damage may occur. A dolly must beused under the unraised wheels when towing or the vehicle must be transported on a flat bed carrier.